2025/03/26 by Dumas, François, Martin, François, Royer, Emmanuel
#FOS: Mathematics #Number Theory (math.NT)
paper · doi:10.48550/arxiv.2503.20375
The notion of double depth associated with quasi-Jacobi forms allows distinguishing,within the algebra of quasi-Jacobi singular forms of index zero, certain significant subalgebras (modular-type forms, elliptic-type forms, Jacobi forms). We study the stability of these subalgebras under the derivations of the algebra of quasi-Jacobi singular forms of index zero and through certain sequences of bidifferential operators constituting analogs of Rankin-Cohen brackets or transvectants.